Collect the browsers also on Android.

Moved the creation of Meek credentials to a function on its own that we
will reuse also with the Android version of MeekTransport.

Store the SOCKS settings as a member, so that we can customize them if
needed before applying them.

Also, cleanup the public interface of TorProcess.
E.g., removed TorProcess.connectionWorked, since we do not use this
information anymore.

Finally, added a TorLauncherUtil.isAndroid.

HTML-ize about:torconnect.

Changed file extension, updated the HTML tag, removed short-tags on tags
that are expected to have a closing tag.
Also, removed the preprocessor and moved the onion pattern to this
commit, since it is used only here.

Move the onion pattern files to the commit of about:torconnect.

We are planning of tempoorarily using about:torconnect on Android, until
the native UX is ready.